7 files changed, 241 insertions, 9 deletions

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index 4b6e29ac0968..e47e52787d32 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -13,7 +13,7 @@ CFLAGS_mmu.o			:= $(nostackp)
 obj-y		:= enlighten.o setup.o multicalls.o mmu.o irq.o \
 			time.o xen-asm.o xen-asm_$(BITS).o \
 			grant-table.o suspend.o platform-pci-unplug.o \
-			p2m.o apic.o
+			p2m.o apic.o pmu.o
 
 obj-$(CONFIG_EVENT_TRACING) += trace.o
 
diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index 70e060ad879a..d03ebfa89b9f 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -72,6 +72,9 @@ static u32 xen_apic_read(u32 reg)
 
 static void xen_apic_write(u32 reg, u32 val)
 {
+	if (reg == APIC_LVTPC)
+		return;
+
 	/* Warn to see if there's any stray references */
 	WARN(1,"register: %x, value: %x\n", reg, val);
 }
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 373dbc9810d1..19072f91a8e2 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -84,6 +84,7 @@
 #include "mmu.h"
 #include "smp.h"
 #include "multicalls.h"
+#include "pmu.h"
 
 EXPORT_SYMBOL_GPL(hypercall_page);
 
@@ -1082,6 +1083,11 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
 	return ret;
 }
 
+unsigned long long xen_read_pmc(int counter)
+{
+	return 0;
+}
+
 void xen_setup_shared_info(void)
 {
 	if (!xen_feature(XENFEAT_auto_translated_physmap)) {
@@ -1216,7 +1222,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = {
 	.write_msr = xen_write_msr_safe,
 
 	.read_tsc = native_read_tsc,
-	.read_pmc = native_read_pmc,
+	.read_pmc = xen_read_pmc,
 
 	.read_tscp = native_read_tscp,
 
@@ -1267,6 +1273,10 @@ static const struct pv_apic_ops xen_apic_ops __initconst = {
 static void xen_reboot(int reason)
 {
 	struct sched_shutdown r = { .reason = reason };
+	int cpu;
+
+	for_each_online_cpu(cpu)
+		xen_pmu_finish(cpu);
 
 	if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
 		BUG();
diff --git a/arch/x86/xen/pmu.c b/arch/x86/xen/pmu.c
new file mode 100644
index 000000000000..1d1ae1b874ea
--- /dev/null
+++ b/arch/x86/xen/pmu.c
@@ -0,0 +1,170 @@
+#include <linux/types.h>
+#include <linux/interrupt.h>
+
+#include <asm/xen/hypercall.h>
+#include <xen/page.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/vcpu.h>
+#include <xen/interface/xenpmu.h>
+
+#include "xen-ops.h"
+#include "pmu.h"
+
+/* x86_pmu.handle_irq definition */
+#include "../kernel/cpu/perf_event.h"
+
+
+/* Shared page between hypervisor and domain */
+static DEFINE_PER_CPU(struct xen_pmu_data *, xenpmu_shared);
+#define get_xenpmu_data()    per_cpu(xenpmu_shared, smp_processor_id())
+
+/* perf callbacks */
+static int xen_is_in_guest(void)
+{
+	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+	if (!xenpmu_data) {
+		pr_warn_once("%s: pmudata not initialized\n", __func__);
+		return 0;
+	}
+
+	if (!xen_initial_domain() || (xenpmu_data->domain_id >= DOMID_SELF))
+		return 0;
+
+	return 1;
+}
+
+static int xen_is_user_mode(void)
+{
+	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+	if (!xenpmu_data) {
+		pr_warn_once("%s: pmudata not initialized\n", __func__);
+		return 0;
+	}
+
+	if (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_PV)
+		return (xenpmu_data->pmu.pmu_flags & PMU_SAMPLE_USER);
+	else
+		return !!(xenpmu_data->pmu.r.regs.cpl & 3);
+}
+
+static unsigned long xen_get_guest_ip(void)
+{
+	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+	if (!xenpmu_data) {
+		pr_warn_once("%s: pmudata not initialized\n", __func__);
+		return 0;
+	}
+
+	return xenpmu_data->pmu.r.regs.ip;
+}
+
+static struct perf_guest_info_callbacks xen_guest_cbs = {
+	.is_in_guest            = xen_is_in_guest,
+	.is_user_mode           = xen_is_user_mode,
+	.get_guest_ip           = xen_get_guest_ip,
+};
+
+/* Convert registers from Xen's format to Linux' */
+static void xen_convert_regs(const struct xen_pmu_regs *xen_regs,
+			     struct pt_regs *regs, uint64_t pmu_flags)
+{
+	regs->ip = xen_regs->ip;
+	regs->cs = xen_regs->cs;
+	regs->sp = xen_regs->sp;
+
+	if (pmu_flags & PMU_SAMPLE_PV) {
+		if (pmu_flags & PMU_SAMPLE_USER)
+			regs->cs |= 3;
+		else
+			regs->cs &= ~3;
+	} else {
+		if (xen_regs->cpl)
+			regs->cs |= 3;
+		else
+			regs->cs &= ~3;
+	}
+}
+
+irqreturn_t xen_pmu_irq_handler(int irq, void *dev_id)
+{
+	int ret = IRQ_NONE;
+	struct pt_regs regs;
+	const struct xen_pmu_data *xenpmu_data = get_xenpmu_data();
+
+	if (!xenpmu_data) {
+		pr_warn_once("%s: pmudata not initialized\n", __func__);
+		return ret;
+	}
+
+	xen_convert_regs(&xenpmu_data->pmu.r.regs, &regs,
+			 xenpmu_data->pmu.pmu_flags);
+	if (x86_pmu.handle_irq(&regs))
+		ret = IRQ_HANDLED;
+
+	return ret;
+}
+
+bool is_xen_pmu(int cpu)
+{
+	return (per_cpu(xenpmu_shared, cpu) != NULL);
+}
+
+void xen_pmu_init(int cpu)
+{
+	int err;
+	struct xen_pmu_params xp;
+	unsigned long pfn;
+	struct xen_pmu_data *xenpmu_data;
+
+	BUILD_BUG_ON(sizeof(struct xen_pmu_data) > PAGE_SIZE);
+
+	if (xen_hvm_domain())
+		return;
+
+	xenpmu_data = (struct xen_pmu_data *)get_zeroed_page(GFP_KERNEL);
+	if (!xenpmu_data) {
+		pr_err("VPMU init: No memory\n");
+		return;
+	}
+	pfn = virt_to_pfn(xenpmu_data);
+
+	xp.val = pfn_to_mfn(pfn);
+	xp.vcpu = cpu;
+	xp.version.maj = XENPMU_VER_MAJ;
+	xp.version.min = XENPMU_VER_MIN;
+	err = HYPERVISOR_xenpmu_op(XENPMU_init, &xp);
+	if (err)
+		goto fail;
+
+	per_cpu(xenpmu_shared, cpu) = xenpmu_data;
+
+	if (cpu == 0)
+		perf_register_guest_info_callbacks(&xen_guest_cbs);
+
+	return;
+
+fail:
+	pr_warn_once("Could not initialize VPMU for cpu %d, error %d\n",
+		cpu, err);
+	free_pages((unsigned long)xenpmu_data, 0);
+}
+
+void xen_pmu_finish(int cpu)
+{
+	struct xen_pmu_params xp;
+
+	if (xen_hvm_domain())
+		return;
+
+	xp.vcpu = cpu;
+	xp.version.maj = XENPMU_VER_MAJ;
+	xp.version.min = XENPMU_VER_MIN;
+
+	(void)HYPERVISOR_xenpmu_op(XENPMU_finish, &xp);
+
+	free_pages((unsigned long)per_cpu(xenpmu_shared, cpu), 0);
+	per_cpu(xenpmu_shared, cpu) = NULL;
+}
diff --git a/arch/x86/xen/pmu.h b/arch/x86/xen/pmu.h
new file mode 100644
index 000000000000..a76d2cf83581
--- /dev/null
+++ b/arch/x86/xen/pmu.h
@@ -0,0 +1,11 @@
+#ifndef __XEN_PMU_H
+#define __XEN_PMU_H
+
+#include <xen/interface/xenpmu.h>
+
+irqreturn_t xen_pmu_irq_handler(int irq, void *dev_id);
+void xen_pmu_init(int cpu);
+void xen_pmu_finish(int cpu);
+bool is_xen_pmu(int cpu);
+
+#endif /* __XEN_PMU_H */
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 86484384492e..2a9ff7342791 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -26,6 +26,7 @@
 
 #include <xen/interface/xen.h>
 #include <xen/interface/vcpu.h>
+#include <xen/interface/xenpmu.h>
 
 #include <asm/xen/interface.h>
 #include <asm/xen/hypercall.h>
@@ -38,6 +39,7 @@
 #include "xen-ops.h"
 #include "mmu.h"
 #include "smp.h"
+#include "pmu.h"
 
 cpumask_var_t xen_cpu_initialized_map;
 
@@ -50,6 +52,7 @@ static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_irq_work) = { .irq = -1 };
 static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
+static DEFINE_PER_CPU(struct xen_common_irq, xen_pmu_irq) = { .irq = -1 };
 
 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
@@ -148,11 +151,18 @@ static void xen_smp_intr_free(unsigned int cpu)
 		kfree(per_cpu(xen_irq_work, cpu).name);
 		per_cpu(xen_irq_work, cpu).name = NULL;
 	}
+
+	if (per_cpu(xen_pmu_irq, cpu).irq >= 0) {
+		unbind_from_irqhandler(per_cpu(xen_pmu_irq, cpu).irq, NULL);
+		per_cpu(xen_pmu_irq, cpu).irq = -1;
+		kfree(per_cpu(xen_pmu_irq, cpu).name);
+		per_cpu(xen_pmu_irq, cpu).name = NULL;
+	}
 };
 static int xen_smp_intr_init(unsigned int cpu)
 {
 	int rc;
-	char *resched_name, *callfunc_name, *debug_name;
+	char *resched_name, *callfunc_name, *debug_name, *pmu_name;
 
 	resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
 	rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
@@ -218,6 +228,18 @@ static int xen_smp_intr_init(unsigned int cpu)
 	per_cpu(xen_irq_work, cpu).irq = rc;
 	per_cpu(xen_irq_work, cpu).name = callfunc_name;
 
+	if (is_xen_pmu(cpu)) {
+		pmu_name = kasprintf(GFP_KERNEL, "pmu%d", cpu);
+		rc = bind_virq_to_irqhandler(VIRQ_XENPMU, cpu,
+					     xen_pmu_irq_handler,
+					     IRQF_PERCPU|IRQF_NOBALANCING,
+					     pmu_name, NULL);
+		if (rc < 0)
+			goto fail;
+		per_cpu(xen_pmu_irq, cpu).irq = rc;
+		per_cpu(xen_pmu_irq, cpu).name = pmu_name;
+	}
+
 	return 0;
 
  fail:
@@ -335,6 +357,8 @@ static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
 	}
 	set_cpu_sibling_map(0);
 
+	xen_pmu_init(0);
+
 	if (xen_smp_intr_init(0))
 		BUG();
 
@@ -462,6 +486,8 @@ static int xen_cpu_up(unsigned int cpu, struct task_struct *idle)
 	if (rc)
 		return rc;
 
+	xen_pmu_init(cpu);
+
 	rc = xen_smp_intr_init(cpu);
 	if (rc)
 		return rc;
@@ -503,6 +529,7 @@ static void xen_cpu_die(unsigned int cpu)
 		xen_smp_intr_free(cpu);
 		xen_uninit_lock_cpu(cpu);
 		xen_teardown_timer(cpu);
+		xen_pmu_finish(cpu);
 	}
 }
 
diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
index 53b4c0811f4f..feddabdab448 100644
--- a/arch/x86/xen/suspend.c
+++ b/arch/x86/xen/suspend.c
@@ -11,6 +11,7 @@
 
 #include "xen-ops.h"
 #include "mmu.h"
+#include "pmu.h"
 
 static void xen_pv_pre_suspend(void)
 {
@@ -67,16 +68,26 @@ static void xen_pv_post_suspend(int suspend_cancelled)
 
 void xen_arch_pre_suspend(void)
 {
-    if (xen_pv_domain())
-        xen_pv_pre_suspend();
+	int cpu;
+
+	for_each_online_cpu(cpu)
+		xen_pmu_finish(cpu);
+
+	if (xen_pv_domain())
+		xen_pv_pre_suspend();
 }
 
 void xen_arch_post_suspend(int cancelled)
 {
-    if (xen_pv_domain())
-        xen_pv_post_suspend(cancelled);
-    else
-        xen_hvm_post_suspend(cancelled);
+	int cpu;
+
+	if (xen_pv_domain())
+		xen_pv_post_suspend(cancelled);
+	else
+		xen_hvm_post_suspend(cancelled);
+
+	for_each_online_cpu(cpu)
+		xen_pmu_init(cpu);
 }
 
 static void xen_vcpu_notify_restore(void *data)